Cardiff Council's 'Usual Suspects' campaign carries the message: "There's no excuse for dropping litter."
The anti-grime crackdown will focus on three main points:
- Dog fouling
- Fly tipping
The council's waste team is also telling dog owners there is a fine of £75 if caught not cleaning up after their dogs.
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Aaron Ramsey has told his English team-mates at Arsenal to beware Wales overtaking them in the FIFA rankings.
Plenty of fine dry weather to come today and prolonged spells of sunshine. A cool easterly breeze will take the edge off the temperatures.
The three-day event in the Welsh capital is expected to attract more than 20,000 visitors.